Check this amazing OpenVDB Clouds free download with 200 Modular elements to use.
These are great to build complex cloud structures, fog banks, etc quickly! these will render in any 3D application that has openVDB implemented. Most common applications are Vray, Houdini, Clarisse, Redshift, Octane Render, etc.
Download free 200 Modular OpenVDB Clouds
2 sets of clouds
Round and Flat
100 high-resolution clouds in each set and low resolution respectively